Traditionally it has been argued that direct benefits from transport investment could be used as a proxy for wider benefits, but it has been raisedthat the impact of transport investment on activity patterns and land useis potentially huge yet rarely considered in transport scheme appraisal and decision-making. This paper uses the rollout of Active Traffic Management (ATM) scheme across the West Midlands (UK) motorway box as a case studyto compare conventional benefits and wider economic benefits in transportappraisal, address this question whether or not these indirect impacts should be brought into transport scheme appraisals, and how this could be done. Using the recent guidelines, issued by Department for Transport (DfT),to estimate these benefits, it has been suggested that wider economic benefits of transport schemes accounted for about an additional 25% benefit over the conventional benefits for various transport investment packages for Leeds city region. Transport Analysis Guidance given by DfT (2003), has provided a methodology to include in the appraisal of transport schemes the wider economic benefits, including impacts on GDP. This guidance was implemented in our forecasting and appraisal work using the strategic model of West Midlands U.K. (PRISM). Commuting travel time saving is used as a proxy of estimating wider economic benefits. One of the key drivers of widereconomic benefits tends to be the employment location changes that the transport scheme or policy causes. Normally these changes are estimated by the use of Land Use Transport Interaction (LUTI) models or Spatially Computable General Equilibrium (SCGE) models. An innovative technique was used to estimate the impact of the transport schemes on employment density for singly constrained models where LUTI or SCGE models are not available. The test results are discussed. For the covering abstract see ITRD E145999
Abstract